1. Field of the Invention
The present invention generally concerns reverse osmosis (RO) systems, and zero-waste RO systems.
The present invention particularly concerns monolithic plumbed sub-assemblies and assemblies used in (i) retrofitting diverse existing non-zero-waste RO systems to become zero waste RO systems, and in (ii) constructing new, modular, zero-waste RO systems.
2. Description of the Prior Art
2.1 General Requirement to Abate Water Wastage Attendant Upon RO
Conventional systems for purifying water by process of reverse osmosis (RO) produce, in addition to purified water, a considerable amount of waste water. This waste water, which is a by-product of the RO process, is also called concentrate water or reject water. It is typically put down the drain of the residence or business in which the RO system is installed. Although called xe2x80x9cwastexe2x80x9d, the waste water is in no way contaminated or unsafe. It simply contains a somewhat higher proportion of the elementsxe2x80x94mostly mineralsxe2x80x94removed from the supply water by the RO process than does the supply water itself. This additional concentration is, of course, resultant from the addition to the waste water of those elements that were previously present in the purified water.
This waste water is of increasing concern, particularly in increasing widespread areas of the world where water is scarce, and even a precious commodity. It is economically inefficient to pump water to distances ranging to thousands of miles, as in the American west, only to put it down the drain. For example, the ratio of concentrate or reject water to purified water can range from about 3:1 to about 15:1 depending on the particular system. This means that for every gallon of purified water produced, from 3 to 15 gallons is considered as concentrate water and is customarily sent to a drain.
It should be understood that recognition of, and concern over, this wastage is not limited to just the inventor of the present application (and a related patent), and to the inventors of still other related patents. Improvements in RO systems have already been made. RO systems sold in the United States up until about 1991 did not necessarily incorporate a shut-off switchxe2x80x94shutting off the flow of water when the tank reservoir of purified water became full, and preventing a RO system from constantly dripping waterxe2x80x94until 1991 when the State of California mandated this wastage-abating feature for all RO systems sold within that state.
Legislatures in several states of the American West now seem poised to act again, and to mandate that newly sold and installed RO systems be of the new xe2x80x9czero wastexe2x80x9d type. The Uniform Plumbing Code (UPC) of the International Association of Plumbing and Mechanical Officials (IAPMO) is presently (circa 2000) in process of being specifically revised so as to set standards for the plumbing of zero-waste RO systems. Unfortunately, such a legislative mandate and/or plumbing code revision will do nothing to abate the cumulative wastage of many millions of RO systems that are already installed. For example, an estimated 3 million RO systems are already installed in the State of California alone.
As fresh water resources become more remote and more costly, certain areas of the world, including areas in America, are very willing to consider further water conservation measuresxe2x80x94especially as would have no discernable performance impact on the water consumer. Zero waste RO systems are such an improvement: the consumer sees no change in the quality of the purified water.
Accordingly, it would be useful if some way could be devised for efficiently and economically retrofitting existing non-zero-waste RO systems to become of the zero-waste type. Such retrofitting would seemingly best use the labor of the homeowner, or a commercial building maintainer, or an installation team of semi-skilled laborers so as to avoid the expense of a journeyman plumber. According to the use of unskilled or semi-skilled labor, the retrofit would desirably be very simple, easy and foolproof. According to (i) the diversity of deployed RO systems, and (ii) the difficulty in eliciting from the building owner any specific information by which any retrofitted items might be selected or customized to a particular pre-installed RO system or a particular building, it would be preferable if any parts used in the retrofit process were (i) universally, or nearly universally, common, with (ii) little wastage of any unused parts.
If the cost of the waste water from an RO system isxe2x80x94as is typical in the U.S. circa 2000xe2x80x94but some few dollars per month, while,the cost of a retrofit kit, even as may be self-installed, isxe2x80x94as may be projectedxe2x80x94some hundreds of dollars then the only owners of non-zero-waste RO systems who will be incentivized to retrofit to a zero waste type will likely be avid conservationists. However, a water district, or a municipality, can dictate retrofit of all non-zero-waste RO systems, provide a monetary incentive if desired. For example, a water district can simply (i) amortize the cost of an RO retrofit kit and its installationxe2x80x94which are both likely offered at no initial charge to district consumersxe2x80x94by amortizing the price therefore over a period of some years on a consumer""s water bill, while (ii) penalizing with higher water rates those consumers who refuse to retrofit to, or install new, zero-waste RO systems.
In the case of consumers self-installing all new zero-waste RO systems, then these systems might typically be subject to cash rebates and other incentives (such as reduced water rates) by the water district; much as similar rebates are currently given in many U.S. water districts for the installation of low flush volume toilets.
However, merely offering a consumer either (i) a reduced rate or, more likely, (ii) the avoidance of a penalty rate, for water consumption if and when a consumer accepts and allegedly installs a zero-waste RO retrofit kit is not a complete solution. Some consumers may accept the kits to get the favorable rate, or avoid the penalty rate, but languish in performing the actual installation. And it is difficult for the water district to confirm installation, by monitoring water consumption or otherwise. It would therefore be useful if this entire retrofit process was well thought through prior to beginning a water-district-wide retrofit effort. It will be seen that the present invention accords for the return of a small and simple, but indispensable, used part from any non-zero-waste RO system to the water district to confirm either (i) retrofit to a zero-waste system, or (ii) dismantlement of the existing non-zero-waste system (whether attendant upon installation of a new zero-waste system or not) The part is normally readily easily unambiguously detectable as used, and it is not realistically feasible for the building owner to buy the (used) part in a hardware store and send to his or her water district as (fraudulent) xe2x80x9cproofxe2x80x9d of compliance.
2.2 Specific Previous Zero Waste RO Systems
The present invention will be seen to be primarily concerned with the physical partitionment, and packaging, of reverse osmosis (RO) systems, particularly of the zero-waste type. Being so focused, the present invention is not primarily directed to the flow paths and apparatus used to realize a zero-waste reverse osmosis systemxe2x80x94of which there are several variant typesxe2x80x94per se. Since it is useful to understand the principles of a zero waste RO system, and of the several variants of such systems, in assessing the structure and function of highly-integrated and compactly-packaged zero-waste RO systems in accordance with the present invention, the reader may care to make reference to the prior art in order to specifically understand zero waste RO systems.
Among this prior art, U.S. Pat. No. 4,626,346 to Hall discloses a reverse osmosis water purification system useful in limited water supply installations such as are found in recreational vehicles, boats and the like which use an unpressurized supply tank for the water source. According to the Hall patent, waste water from the reverse osmosis unit is recycled back to the supply tank to conserve water.
U.S. Pat. No. 5,639,374 for a WATER-CONSERVING PRESSURE-MAINTAINING REVERSE OSMOSIS SYSTEM to inventors including the selfsame Monroe who is the inventor of the present invention concerns a reverse osmosis water purification system in which the concentrate water normally produced by the process is not disposed of by routing it to a drain line or otherwise, but is redirected to the main water supply. The system includes the well-known components of a reverse osmosis membrane, pre-filters which are installed ahead of the reverse osmosis membrane, and an appropriate tank to store the purified water. In addition, the system includes a pump and associated pressure sensing device for increasing the pressure of the incoming non-processed water to the reverse osmosis unit, and a pipe to carry the concentrate water from the reverse osmosis unit to the incoming main water supply, be it either a cold or hot water line. Additionally included is a one-way check valve in the concentrate water line, and a sensing device in the purified water storage tank to turn the pump off whenever the quantity of water in the tank exceeds a predetermined amount.
Notably in construction of the Monroe, et al. system, and as an important feature carried over into the preferred embodiments of systems in accordance with the present invention, a flow connection between the (i) waste outlet port of a RO unit, and (ii) a pressurized water source, is both unconstricted and unrestricted. By this unconstricted and unrestricted connection the waste, or concentrate, water from the RO unit encounters during its entire conveyance the full and exact pressure of the supply water. Being that there is no pressure differential, nor any (pressure-differential-inducing) obstruction, within the flow conduit, there is no build-up of contamination in the flow pathxe2x80x94which is operationally important.
U.S. Pat. No. 5,879,558 to Monroe, et al., for a WATER CONSERVING REVERSE OSMOSIS UNIT AND METHOD OF OPERATING IT likewise discloses a reverse osmosis water purification system in which the concentrate water which is normally produced by the process is not disposed of by routing it to a drain line or otherwise, but is instead redirected to the main water supply. The system includes the well-known components of a reverse osmosis membrane, pre-filters which are installed ahead of the reverse osmosis membrane, and an appropriate tank to store the purified water. In addition, the system includes a pump and associated pressure sensor for increasing the pressure of the incoming non-processed water to the reverse osmosis unit, means for directing the concentrate water from the reverse osmosis unit to the incoming main water supply (cold), or to a hot water line. Additionally included is a one-way check valve in the concentrate water line, and a sensor sensing the pressure of water in the storage tank and turn the pump off whenever the pressure exceeds a predetermined value.
As with the ""374 patent, a concentrate water pipe conveys concentrate water from a reverse osmosis unit to a downstream location of a water source that is essentially at the supply pressure. Although this concentrate water pipe includes a check valve for preventing water from the water source to flowing into the reverse osmosis unit (at the wrong pointxe2x80x94the concentrate water output) such as under transient pressure surges, this pipe is again without any substantial pressure drop or flow restriction whatsoever. Namely, the check valve neither produces any substantial flow restriction nor any substantial pressure drop to the normal, outward, flow of concentrate water.
2.3 Integrated Packaging of Multiple Components of RO Systems
The present invention will be seen to be concerned with the partitionment, and packaging, of the multiple components of a reverse osmosis system (preferably of the zero-waste type), particularly such partitionment and packaging as provides a higher degree of integration than heretofore, simplifying both installation, and/or retrofit, of an RO system so greatly that these tasks may be reliably performed by amateurs.
A step towards the integration of several components of a RO system into a single unit is shown in U.S. Pat. No. RE 35,252 to Clack, et al., for a FLUID FLOW CONTROL DEVICE FOR WATER TREATMENT SYSTEMS. The Clack, et al., patent shows new and improved filtration purification or water treatment systems for providing improved purified drinking water at a point of use which systems are provided with a substantially leak-free fluid flow control device to which the other filtration purification system elements may be mated and engaged. Other system elements may include various filters or filter modules, as well as system leads for conveying (i) incoming tap water in, (ii) outgoing waste water out to drain and (iii) purified water from the filter section to a storage tank until desired for use. The fluid flow control device is preferably a unitary thermoplastic body formed from a pair of interconnecting halves, the body having (i) a number of discrete fluid flow passages extending therein, and (ii) mating grooves by which the halves are joined. In a preferred embodiment, the fluid flow control device includes each of (i) integrally formed input/output connector features, (ii) filter-receiving socket portions and (iii) an automatic shut off valve disposed in fluid flow communication with certain ones of the passages.
The present invention contemplates a certain, particular, partitionment and packaging of the multiple components of RO systemsxe2x80x94particularly as are used in RO systems of the zero waste typexe2x80x94for use in (i) retrofitting diverse existing non-zero-waste RO systems to become zero waste RO systems, (ii) constructing new RO systems, particularly of the zero-waste type. The RO system so partitioned, and the RO system components so packaged, are characterized by being but few in number, and highly integrated.
Characteristically the plumbed connections of a zero-waste reverse osmosis system in accordance with the present inventionxe2x80x94while retaining the RO filter, purified water storage tank, and numerous valves and gauges characteristic of an RO systemxe2x80x94are reduced to three (only) monolithic sub-assemblies, and these three sub-assemblies are themselves preferably physically co-mounted, and readily flow-connected together into one single assembly. Still more particularly, the preferred three sub-assemblies and assembly are preferably made of plastic, and typically serve in combination to integrate three major flow paths and eight associated RO components. A practitioner of the RO system design and fabrication arts will immediately appreciate that an RO system component normally has at least one (as in the case of a gauge) or two (as in the case of a valve) plumbed connections. As just stated, there are typically some eight RO system components. Therefore, the sub-assemblies of the present invention which, when delivered into service, need be plumbed only at their xe2x80x9cinputxe2x80x9d and xe2x80x9coutputxe2x80x9d, can be fairly described as being xe2x80x9chighly integratedxe2x80x9d.
The entire present invention is thus more concerned with the physical partitionment and physical packaging of (zero waste) RO systems than with the theory and the plumbing flow paths of these systems. This means that (i) the plumbed pathways of zero-waste RO systems realized by application of the present invention are not represented to be unique, and (ii) the present invention is not concerned with new methods, or new flow paths, for the conduct of zero-waste RO. Instead, the partitionment and packaging concerns of the present invention are directed to sub-assemblies and assemblies that, being astutely designed, serve to support both (i) the efficient, economic and reliable retrofitting of diverse pre-existing non-zero-waste RO systems to become zero-waste RO systems by but modest use of unskilled or semi-skilled labor, and also, (ii) the construction of new RO systemsxe2x80x94particularly of the zero-waste typexe2x80x94having an unparalleled high degree of components integration so as to better support improved economies-of-installation, system reliability, and system longevity.
The new-form, highly-integrated, (zero-waste type) RO system sub-assemblies and assemblies in accordance with the present invention are visually distinguishable from previous RO systems in that, inter alia, the number of different assemblies or sub-assemblies in the system is greatly reduced, typically from as many as ten or more (i.e., 10+) to only three or four. In a simplest terms, system fluid flow paths that used to be plumbed externally between flow-connected system components are brought into the interiors of monolithic subassemblies, and functional components of the (zero-waste type) RO system are threadingly connected through fittings.
Meanwhile, simultaneously, (ii) all system operator controls and indicators are ergonomically located in an orderly and accessible fashion. For example, some three pressure gauges typically within a single preferred sub-assembly in accordance with the present invention are all located neatly in a line, and are oriented so that the nominal correct pressure reading on each gauge produces an equal angular displacement of that gauge""s pointer indicator against a green-red (good-bad) scale. Accordingly, the correct operation of the system is discernable at a glance. All owner/user manipulatable valves and the like, and all system components, are similarly clearly and logically situated and marked, removing much of the mystery as to what is what and, more importantly, permitting troubleshooting and repair directions to be given to amateurs, as in xe2x80x9ctwist the red valve clockwise in the direction of the red arrowxe2x80x9d.
The high degree of system integration permitted by the monolithic sub-assemblies and assembly of the present invention supports, among other things, the conversion of diverse existing non-zero-waste RO systems may typically be converted to zero-waste RO systems simply by disconnecting three only existing plumbing unions (which are normally of a quite standard nature), and re-connecting each of the six ends so created (as may be extended by use of simple extensions, and/or adapted by simple adapter fittings, as is infrequently necessary) to, most typically, the preferred three new monolithic sub-assembles that are themselves mounted to a single new frame or back plane, forming thereby an assembly that most typically flow-connects, most typically, some eight or more different components.
After (i) flow connections are realized by the simple turning of fittings, (ii) the preferred major assembly, which contains an electric pump, is plugged to power, and (iii) a system water supply is turned back on, the entire job of retrofitting a zero-waste RO system is finished. Such simplicity of installation is not typical of previous RO systems of any type, and the inventive concept of efficiently retrofitting existing non-zero-waste RO systems using monolithic sub-assemblies and assemblies to make these RO system into the zero-waste type is not known by the inventor to have previously existed.
1. Monolithic (Sub-)Assemblies, Particularly for Making a Zero-waste Reverse Osmosis System
In one of its aspects the present invention is embodied in one or more (first-level, or sub-) assemblies, The (sub-) assemblies may be, and preferably are, packaged as a kit for use in retrofitting a pre-existing non-zero-waste reverse osmosis system to become zero-waste. They may also be effectively used in new construction RO systems, particularly of the zero-waste type. All (sub-) assemblies are thus used in a reverse osmosis system flowing water between an inlet port receiving pressurized unpurified water and a first outlet port flowing purified water and a second outlet port flowing waste water.
One such monolithic (sub-) assembly (xe2x80x9csub-assembly 1xe2x80x9d) is usable in a portion of the reverse osmosis system between the inlet port and a reverse osmosis membrane vessel.
This (sub-) assembly 1 includes (i) a monolithic molded body defining a fluid flow channel between (1) an input portal suitably connected externally to the body to a pressurized flow of unpurified water and (2) an output portal suitably connected externally to the body to a reverse osmosis membrane vessel. It further includes (ii) a first portal, molded within the body, communicating fluid pressure from the fluid flow channel within the body to a pressure switch external to the body, and (iii) a second portal, molded within the body downstream of the first portal, communicating fluid pressure from the fluid flow channel within the body to a pressure gauge external to the body.
By this construction, and this coaction, the (i) body flow connects a pressurized flow of unpurified water to a reverse osmosis membrane vessel while communicating fluid flow pressure to both an external pressure switch and an external pressure gauge.
Preferably the (ii) first portal communicates fluid pressure from the fluid flow channel within the body to an electronic pressure switch that serves to control a valve for cutting off fluid flow to the assembly, and to the reverse osmosis system, when and for so long as a predetermined pressure is exceeded.
Another, separate, such monolithic (sub-) assembly (xe2x80x9csub-assembly 2xe2x80x9d) is usable in a portion of a reverse osmosis system flowing water between an inlet port receiving pressurized unpurified water and a first outlet port flowing purified water and a second outlet port flowing waste water.
This monolithic (sub-) assembly 2 usable in a portion of the reverse osmosis system between purified water output from a reverse osmosis membrane vessel and the first outlet port includes (i) a monolithic molded body defining a fluid flow channel between (1) an input portal suitably connected externally to the body to a pressurized flow of purified water from a reverse osmosis membrane vessel and (2) an output portal flowing purified water. It further includes (ii) a first portal, molded within the body, communicating fluid pressure from the fluid flow channel within the body to a pressure switch external to the body, and (iii) a check valve in the fluid flow channel within the body for preventing any flow of fluid from the output portal to the input portal.
By this construction, and this coaction, the (i) body of the second (sub-) assembly serves to unidirectionally flow connect a pressurized flow of purified water from a reverse osmosis membrane vessel to an outlet portal while also communicating fluid flow pressure to an external pressure switch. The (iii) check valve is preferably press fitted within the fluid flow channel of the (i) body.
Still yet another, separate, such monolithic (sub-) assembly (xe2x80x9csub-assembly 3xe2x80x9d) is usable in reverse osmosis system flowing water between an inlet port receiving pressurized unpurified water and a first outlet port flowing purified water and a second outlet port flowing waste water.
This monolithic (sub-) assembly 3 usable in a portion of the reverse osmosis system between a waste water output from a reverse osmosis membrane vessel and the second outlet port includes (i) a monolithic molded body defining a fluid flow channel between (1) an input portal suitably connected externally to the body to a pressurized flow of purified water from a reverse osmosis membrane vessel and (2) an output portal flowing waste water. It further includes (ii) a first portal, molded within the body, communicating fluid pressure from the fluid flow channel within the body to a first pressure gauge external to the body, and (iii) a check valve, located in the fluid flow channel of the body downstream from the first portal, preventing any flow of fluid from the output portal to the input portal.
By this construction, and this coaction, the (i) body flow unidirectionally connects a pressurized flow of purified water from a reverse osmosis membrane vessel to an outlet portal while communicating fluid flow pressure to an external pressure switch.
This third (sub-) assembly preferably also has (iv) a second portal, molded within the body downstream from the check valve, communicating fluid pressure from the fluid flow channel within the body to a pressure gauge external to the body. The (iii) check valve is preferably of the back-to-back dual type, and is preferably molded within the fluid flow channel of the (i) body. The check valve may alternatively be press fitted within the fluid flow channel of the body.
It is clear the (sub-) assemblies 1-3 are similar. They may all be usedxe2x80x94connected as appropriate including to each otherxe2x80x94in a single RO system. They are thus commonly described as xe2x80x9csub-assembliesxe2x80x9d, and their combination as an xe2x80x9cassemblyxe2x80x9d, although it is clear the xe2x80x9csub-assemblesxe2x80x9d 1-3 may be individually beneficially employed.
The plumbed connections to the inlet portal and to the outlet portal or any of the sub-assemblies 1-3 may be either (i) press fitted and/or (ii) threaded and screwed.
Any of the sub-assemblies 1-3 may have and present at least one tab by which the assembly is suitably physically mounted to a backboard.
Finally, any and all of the sub-assemblies 1-3 may be, and preferably are, used in a zero-waste reverse osmosis system.
These and other aspects and attributes of the present invention will become increasingly clear upon reference to the following drawings and accompanying specification.